Field of Invention
The invention relates to a syringe for multi-component materials, preferably a single-fill syringe for multi-component materials, to a method of activating a syringe, to a mixing and dispensing apparatus and to a multi-component cartridge.
Background Information
Common syringes are simple pumps which are typically used for the metering of small amounts of material and generally comprise a tube for the material to be metered, a plunger that fits tightly into the tube and by means of which a material present in the tube can be discharged via a needle or nozzle attached at the opposite end of the syringe. The tube is frequently also used as a storage chamber for materials.
Syringes for multi-component materials also exist. The materials to be dispensed are typically a matrix material and a hardener. The filled cartridges come in different sizes referred to as 1:1, 2:1, 4:1 and 10:1 etc., the numbers specifying the ratios of the amounts of each of the two materials that are to be dispensed. The reason for these different sizes is to allow a wide variety of different compositions to be mixed and dispensed. For example some compositions require more hardener and some require less hardener. Also some compositions require more mixing.
Two-component materials are typically used as impression materials, e.g. on the formation of dental impressions, such impression material is e.g. sold under the tradename Affinis, as a cement material for prosthetic restorations, e.g. sold using the tradename Per-maCem, as a temporary cement for trial cementing restorations or for cementing temporary crowns, e.g. sold using the tradename Temp-Bond. Further applications of two-component materials are in the building industry where they are e.g. used as a replacement for mechanical joints that corrode over time. Adhesive bonding can be used to bond products such as windows and concrete elements. The use of multi-component protective coatings, for example moisture barriers, corrosion protection and anti-slip coatings, is also becoming increasingly common.
Dispensing apparatus for multi-component materials are also known and range from multiple application devices if they are used in combination with e.g. replaceable mixing tips, to single application devices. On discharging these multi-component materials, the different components have to be combined with one another in order for these to react.
Two-component materials are known, for example in the dental field or in the building sector. The two-component materials typically only cure when they come into contact with one another. However, these components are chemical compositions and can degrade if they are exposed to air for a considerable period of time. For this reason pre-filled syringes and cartridges have to be provided with a closure which prevents the materials from premature aging and which ensure a certain storage life of the components. This storage capability must nevertheless be easily accessible on a dispensing of the materials. For one time applications the closure need not be re-sealable for multiple dispensing applications the closure has to be re-sealable.